Effect of low-pass filtering on passivity and rendering performance of series elastic actuation

Kenanoğlu, Özgür Taylan and Kenanoglu, Celal Umut and Patoğlu, Volkan (2023) Effect of low-pass filtering on passivity and rendering performance of series elastic actuation. IEEE Transactions on Haptics . ISSN 1939-1412 (Print) 2329-4051 (Online) Published Online First https://dx.doi.org/10.1109/TOH.2023.3273168

Full text not available from this repository. (Request a copy)


We study the effect of low-pass filtering on the passivity and performance of series elastic actuation (SEA) under velocity-sourced impedance control (VSIC) while rendering virtual linear springs and the null impedance. We analytically derive the necessary and sufficient conditions for the passivity of SEA under VSIC with filters in the loop. We demonstrate that low-pass filtered velocity feedback of the inner motion controller amplifies the noise at the outer force loop, necessitating the force controller also be equipped with low-pass filtering. We derive passive physical equivalents of the closed-loop systems to provide intuitive explanations of the passivity bounds and to rigorously compare the performance of controllers with and without low-pass filtering. We show that, while low-pass filtering improves the rendering performance by decreasing the parasitic damping effects and allowing for higher motion controller gains, it also introduces more strict bounds on the range of passively renderable stiffness. We experimentally verify the passive stiffness rendering bounds and performance improvements for SEA under VSIC with filtered velocity feedback.
Item Type: Article
Uncontrolled Keywords: Actuators; coupled stability; Filtering; Force; haptic rendering; Impedance; low-pass filtering; Low-pass filters; passivity; Physical human-robot interaction; physical realization; Rendering (computer graphics); series elastic actuation; Springs; velocity-sourced impedance control
Divisions: Faculty of Engineering and Natural Sciences
Depositing User: Volkan Patoğlu
Date Deposited: 06 Aug 2023 20:17
Last Modified: 06 Aug 2023 20:17
URI: https://research.sabanciuniv.edu/id/eprint/47338

Actions (login required)

View Item
View Item